This invention relates to energetic materials and more particularly to methods of producing energetic materials from metals and fluoropolymers.
Pyrotechnics are mixtures of substances that produce noise, light, heat, smoke, or motion when ignited. They are used in matches, incendiaries, and other igniters; in fireworks and flares; in fuses and other initiators for primary explosives; in delay trains; and for powering mechanical devices. Military pyrotechnics include a wide range of devices for illumination, signaling, incineration, and gas generation. Military pyrotechnic devices are characterized by more rugged construction and greater resistance to adverse environmental conditions with concomitant higher cost, reliability, and safety than are civilian pyrotechnics.
Magnesium/Teflon/Viton (MTV) pyrotechnics are used by the Armed Forces to manufacture rocket motor igniters and flare decoys. MTV is currently manufactured using the shock-gel process in which: (1) the Viton binder is dissolved in acetone; (2) the magnesium and Teflon particles are added to the Viton/acetone solution to form a slurry; (3) and hexane is added to the slurry to shock the slurry and precipitate the Viton out of solution onto the surfaces of the magnesium and Teflon particles. The solvent is then decanted from the mixture and the procedure is repeated to ensure that all the remaining acetone is washed from the pyrotechnic material. Although the process is extremely effective in coating the magnesium and Teflon, it is a lengthy batch process which requires an extremely large quantity of solvent (acetone and hexane) to coat the magnesium and Teflon with the Viton binder. It takes five 55-gallon drums of solvent to process 200 pounds of MTV. The collected acetone and hexane mixture must be disposed of as hazardous waste due to the toxic nature of the solvent.
It would be desirable to provide an method of producing high quality energetic materials composed of a mixture of magnesium (or magnesium alloys, aluminum, aluminum alloys, etc.) particles and polytetrafluoroethylene (e.g., Teflon) particles in a vinylidene fluoride-hexafluoropropylene copolymer (e.g., Viton A, Fluorel) binder without generating large volumes, of hazardous waste.